Introduction

If the phonology of an established language includes a set of rules which relate internal representations to surface forms, to understand a developing phonology one must infer the child's stored lexical forms from observations of his physical expression of those forms. Child phonologists would then seek to determine the relationship between stored and articulated forms, hence, the nucleus of the child's phonology. Those wishing to understand deviant utterances would additionally look for discrepancies between the child's internal representations and the prevailing forms in his environment.

As all phonologists need to know something of children's internal representations, it is embarrassing that most of us know nothing substantive about them. Even those who have diligently studied children's perception of speech know little of their internal representations of words. In the face of this, are phonologists hesitant to make statements about children's rule systems? Are developmental phonologists busily applying the techniques of cognitive psychology to reconstruct children's stored lexical forms? These would seem to be appropriate behaviours under the circumstances, but in fact many phonologists have suggested – and still appear to assume – that children ‘have the adult form as their internal representation’.

Peters (1974) has asked what it means to say ‘the adult form’ when there are lots of surface forms for any given word, within and across adult speakers.